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Hi Duncan,
Martin here from California (aka Hassleweed on the Locost USA forum). You were kind enough to introduce yourself on my Tesla powered Seven build. I wanted to thank you as I now am going to use the Chevy Volt battery pack. The batteries I was planning to use have been shutdown - LG Chem has been issuing cease and desist letters - and so I have ordered a 2nd Gen Volt pack. Thank you for the suggestion. I'll be digging around your blog for how to get it working!
Cheers
Martin
 

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Discussion Starter · #322 ·
Hi Guys
Bit of a gap - went to a Tarmac Autocross at Teretonga yesterday

Car went well
But I have identified a problem - its not been that quick at these events
Yesterday it was blindingly obvious that my front grip was severely lacking!!


My back tyres are competition tyres - very grippy
My front tyres are the ones that were on the rims when I got them! - normal saloon tyres at least 12 years old

I have ordered another pair of sticky tyres - these are slightly taller and wider than the ones I have just now so they will go on the back and my lovely Nittos will go on the front

Its our annual Drag races on Sunday the 21st of February - will see how that goes
 

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Nice Work Duncan. Looks quick on a tight course. I've probably mentioned it before but bang for buck I love Nankang AR1 for a light car. Apparently they aren't so good on a heavier car.
 

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Discussion Starter · #325 ·
Nice Work Duncan. Looks quick on a tight course. I've probably mentioned it before but bang for buck I love Nankang AR1 for a light car. Apparently they aren't so good on a heavier car.
Just picked up the tyres - haven't paid for them yet!
They are "NEXEN"
I could not get "NITTO" in the right size and the local expert said these were good
Now I have the 225/45/17 Nitto - to go on the front - and the 235/45/17 Nexen - for the rear
These are asymmetric - I need to put the correct wheel and tyre on the correct corner

Will see how grippy the new rear tyres are at our drags on the 21st February
 

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Discussion Starter · #326 ·
Hi Guys
Last Sunday we had our annual 1/8th mile drag race

Did not do as well as before - possibly the tyres were too new!

A Hybrid 4WD Porsche was there to beat me - and he did!

My best time was 7.94 seconds and 96 mph (last year I got 7.83 seconds and 96 mph)
The Porsche got 7.88 seconds and 93 mph

I set up my cheapo GoPro knock off to look at my instruments - interesting




121946


"Series 3" was my fourth run - I spun the tyres and had to lift - that was half a second slower than the third run !!

My very first run I set the camera incorrectly - AND I spun the tyres half of the way down the strip and nearly went into the ditch

The "error bars" on those readings are quite large - just me taking the numbers from the videos

I seem to have increasing SAG until the controller maxes out at about 100 kph - only 20% - I was expecting more! - then steady away for 2 or 3 seconds before I lift
 

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Discussion Starter · #327 ·
Grass event today
Our fourth attempt at running our Christmas autocross and barbeque - the weather gods vetoed the previous three goes

Great fun
The grass remained a bit slippery but I had a great time





Running at 40% power - and I was nowhere near full throttle
 

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Discussion Starter · #328 ·
Another day out at Teretonga - reminded me of Scotland it rained on and off and I got wet





I have the new NEXEN's on the back and the NITTOS on the front - made a HUGE difference the car just felt so much more "planted"
And I moved from the back quarter of the results to the front quarter

Question
Spring Rates
I'm running
100 lb/inch on the front which give me wheel frequency of 100 CPM
125 lb/inch on the rear which give me wheel frequency of 94 CPM

With the amount of roll I'm getting (damn all) I'm thinking of changing to

70 lb/inch on the front which give me wheel frequency of 78 CPM
100 lb/inch on the rear which give me wheel frequency of 84 CPM

Comments??
 

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Another day out at Teretonga - reminded me of Scotland it rained on and off and I got wet





I have the new NEXEN's on the back and the NITTOS on the front - made a HUGE difference the car just felt so much more "planted"
And I moved from the back quarter of the results to the front quarter

Question
Spring Rates
I'm running
100 lb/inch on the front which give me wheel frequency of 100 CPM
125 lb/inch on the rear which give me wheel frequency of 94 CPM

With the amount of roll I'm getting (damn all) I'm thinking of changing to

70 lb/inch on the front which give me wheel frequency of 78 CPM
100 lb/inch on the rear which give me wheel frequency of 84 CPM

Comments??
It's always a trade-off. More suspension travel can allow the alignment to change. More suspension travel can allow the tires to continue gripping with dynamic weight transfer. After watching a few of your runs, I'd say try softer and see if it matches your style of driving (and what happens to the times). Especially during the slaloms, I could see potential gains by allowing more
movement.
 

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Discussion Starter · #330 ·
On Saturday I took my Device to a 1/4 mile drag strip
Could not stop the tyres spinning at the start - their rules would not let me do a burnout
Bit disappointing - managed 13.45 seconds and 104 mph
Acceleration is definitely dropping off!
It takes 7.9 seconds and 1/8th mile to get to 96 mph - the next 5 seconds and 1/8th mile only add another 8 mph

Note this is the European/Kiwi style - we do not allow the 1 ft run up that seems to be allowed in the USA
 

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On Saturday I took my Device to a 1/4 mile drag strip
Could not stop the tyres spinning at the start - their rules would not let me do a burnout
Bit disappointing - managed 13.45 seconds and 104 mph
Acceleration is definitely dropping off!
It takes 7.9 seconds and 1/8th mile to get to 96 mph - the next 5 seconds and 1/8th mile only add another 8 mph
It's not just the slow acceleration in the second 1/8th that hurts: if you had hit the 1/8th at your usual 96 MPH and continued up to 104 MPH at constant acceleration, it would have taken only another 4.5 seconds for the second 1/8th (for a total of 12.4 seconds if the first 1/8th took 7.9 s), so presumably in this run the first 1/8th wasn't that fast due to the launch traction issue.
 

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On Saturday I took my Device to a 1/4 mile drag strip
Could not stop the tyres spinning at the start - their rules would not let me do a burnout
Bit disappointing - managed 13.45 seconds and 104 mph
Acceleration is definitely dropping off!
It takes 7.9 seconds and 1/8th mile to get to 96 mph - the next 5 seconds and 1/8th mile only add another 8 mph

Note this is the European/Kiwi style - we do not allow the 1 ft run up that seems to be allowed in the USA
Hi Duncan, I've personally never drag raced so I don't have experience with the rules but I've never been to a drag racing event that didn't allow a tire "warm-up" (burn out),.. In fact I'd say it seems like it's encouraged here in Oz at least.

Every hillclimb event I've ever raced in has always allowed a "single continuous forward moving tire warm-up" strictly within a set portion of the pre-start-line area. (Prior to getting to start line).

Was this rule applied to your vehicle only? Or was nobody allowed to warm-up tires pre run?

Thanks for sharing your Motorsport with us, helping us all stay motivated back in the garage. Cheers.
 

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Discussion Starter · #333 ·
Hi Duncan, I've personally never drag raced so I don't have experience with the rules but I've never been to a drag racing event that didn't allow a tire "warm-up" (burn out),.. In fact I'd say it seems like it's encouraged here in Oz at least.

Every hillclimb event I've ever raced in has always allowed a "single continuous forward moving tire warm-up" strictly within a set portion of the pre-start-line area. (Prior to getting to start line).

Was this rule applied to your vehicle only? Or was nobody allowed to warm-up tires pre run?

Thanks for sharing your Motorsport with us, helping us all stay motivated back in the garage. Cheers.
I do a burn out at our annual 1/8th mile drags
But this was with a different motor club and their rules are
(1) Only their club members get to do a burnout
(2) Only cars that do less than 12 seconds get to do a burnout

So no burn-out for me!
 

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Discussion Starter · #334 ·
On Saturday I did a "Bent Sprint" at Teretonga

That is a higher speed event and I needed to get an actual speed license
Great Fun
I was not that quick ended up 13th out of 16!!

I moved my camera downwards to try and see the speeds - not a great success but you can see sometimes -
Straight up and down is 100 kph


Still with the existing springs - I have a softer pair but not fitted them yet

The four full power runs ate my charge - not enough for a fifth run and the fourth run was slightly speed limited
 
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